This research on the chemistry and biology of somatostatin will focus on two main areas. Firstly, a continuing investigation of the physiological roles of the hormone particularly with respect to its many effects on gut and pancreatic secretions. Secondly, structure-activity studies on synthetic analogues. This will be aimed at elucidating the mechanisms of action of the peptide, developing analogues with greater specificity of action which could be of value in the treatment of a variety of disease including diabetes mellitus, acromegaly and gastric ulcers, and designing analogues with increased, and preferably, prolonged in vivo activities. In addition, suitable analogues will be screened for antagonist properties.